This is a story about numbers. A lot of them.

But numbers are what the U.S. Census Bureau is about. And for Utah's part of the federal agency's 2010 census plan, the first number is 3,050.

That's how many Utahns will be temporarily employed -- for varying lengths of time from late February into August. -- in three Wasatch Front 2010 Census call centers, according to Cathy Lacy, director for the Denver Regional Census Office. About 1,500 will be employed in Sandy, 1,100 in Murray and 450 in Ogden.

On top of that, Utah's three local U.S. Census offices -- Salt Lake City, Ogden and Provo -- are each hiring 1,000 enumerators, or temporary workers who will be assigned to deliver forms to homes whose residents do not receive traditional mail at a street address, such as those holding post office boxes or who collect mail through general delivery.

Those hires bring the total for temporary census workers in the Beehive State to 6,050. The numbers can fluctuate, Lacy said, depending on Utahns' response to the every-10-year population count.

The numbers did fluctuate Wednesday as officials scrambled to pull together all of the hiring elements for the different types of positions. Late in the day, Lacy got final confirmation of the 6,050 jobs to be filled during the next two months.

Officials do not know how many Utah homes will need enumerators' visits, but preliminary estimates top 13 million nationwide. Across the country, 134 million housing units will receive census forms via the U.S. Postal Service beginning in mid-March, according to Tom Messenbourg, the U.S. Census Bureau's deputy director.

He was in Sandy Wednesday to dedicate the larger call center that has been set up in buildings that formerly served as a Discover Card call center. The Sandy operation is being run by two subcontractors -- Vangent Inc. and Affiliated Computer Services. A third company, Convergys, is in charge of the Murray and Ogden call centers.

Messenbourg said the Utah call center operations are part of 11 centers across the United States employing 9,000 workers. The Sandy facility is expected to receive the biggest volume of calls of any of the centers nationally. Seven million to 8 million calls are expected to come into the 11 centers from mid-March to mid-April. Then, workers will shift to making outgoing calls; those numbers are protected at 15 million into August.

Initially, the incoming calls will be from people who have questions about the census forms.

Nationally, said Messenbourg, there are another 13 million residents who might not have mail delivery at their home addresses. For them, "additional workers will go out, verify addresses and leave a form."

That form, he said, contains 10 questions.

"It's pretty straight-forward. One question will ask for the number of people in a given household and then ask for a breakdown of those numbers by ethnicity and other factors."

One feature this year is distribution of dual-language forms within 4,000-member "census tracts" where at least 20 percent are defined by the Census Bureau as Hispanic. People with questions can be assigned to a call center employee who speaks either English, Spanish, Chinese, Korean, Vietnamese or Russian.

The outgoing calls to residents are designed to clear up any discrepancies uncovered in individual forms once they are scanned, Messenbourg said. Contractors at processing centers elsewhere can scan 2 million forms a day by using optical-character-recognition software, and data needing clarification will be sent to call centers on high-speed, fiber-optic lines.

Coordinating all of this is Lockheed Martin, the bureau's primary contractor responsible for organizing the call centers nationally.

The U.S. Census Bureau is launching a national advertising campaign scheduled to begin Sunday during the "Golden Globe Awards" on NBC. Viewers will then see a series of ads "running nonstop between now and May," Messenbourg said.

jkeahey@sltrib.com